CH4/CO2 reforming over highly active catalysts that is Ce-promoted Ni supported on KIT-1 with wormlike pore structure

Resumo

A new type of Ce-promoted Ni catalyst with KIT-1 as the support is prepared by using a sol-gel method. The catalyst exhibits excellent catalytic activity and superior stability in CO₂ reforming of methane (CH₄/CO₂ reforming) reaction. Effects of CeO₂ and KIT-1 with wormlike pore structure on catalytic activity are investigated by N₂-physisorption, XRD, H₂-TPR and TG techniques. The results indicate that the wormlike pore structure of KIT-1 is in favor of the high dispersion of metallic particles, and the doping of CeO₂ promotes the dispersion of Ni particles on the surface of support, which inhibits the agglomeration and sintering of active particles in CH₄/CO₂ reforming reaction. Moreover, carbon deposition on the surface of the catalysts decreases obviously due to the introduction of CeO₂. Experimental results during CH₄/CO₂ reforming show that the catalyst presented better catalytic performance than other Ni-based catalysts at 700°C and a gas hourly space velocity (GHSV) of 32 L g_cat^–1 h^–1, which is attributed to better textural property of KIT-1, better dispersion of active species, and lower carbon deposition. Especially, 6% Ce-NiO/KIT-1 shows the best catalytic activity among the series of catalysts prepared in this experiment.